Hydraulic press.



Patented Jan. 23, I900.

W. &. C. SELLERS,&. W. LEWIS.

HYDRAULIC PRESS.

("o Modal) (Application filed. July 11, 1895.) 9 sheets-sheet E'IE l N.a, a 31 11 l I29 W Q 58 L Egg 66 28 40 0 """l 5/ T L l 4 ,2?

WITNESSES. W $795M m: prams PEYER co, FHOTO-LIYHO, WASNWOTON, u. c,

Patented Jan. 23, I900. LEWIS.

W. & U. SELLERS & W.

HYDRAULIC PRESS.

9 M m l 0 M- r a." u

i Ii W/TA/ESSES' No. 642,009. Patented Jan. 23, I900. W. &. C. SELLERS &W. LEWIS.

HYDRAULIC PRES S.

(Application filed July 11, 1895.)

9 Sheets-Sheet 3.

(No Model.)

mums psrzns ccv wormuwo, WASHINGYON,

No. 642,009. Patented Jan. 23, 1900. w. & c. SELLERS & w. LEWIS.

HYDRAULIC PRESS.

(Application filed July 11, 1895.)

9 Sheets-Sheet 4,

(No Medal.)

FIG. 12.

FIG. 13..

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M T/VESSES NORRIS perms co, wore-um), WASNVNOTON, n c.

No. 642,009. Patented Jan. 23, I900. W. a c. SELLERS & W. LEWIS.HYDRAULIC PRESS.

(Application filed. July 11, 1895.) (N0 Modei.) 9 SheetsShBet '5.

Iii H M FIG. 15.

l/V VE/VTORS:

m E- Ncnms PETE us ca woroumo" wunms'rou. o. c.

(No Model.)

FIE-3. 1E.

W/T/VESSES:

Patented Jan. 23, I900. W. 8:. C. SELLERS & W. LEWIS. HYDRAULIC PRESS.

(Application filed. July 11, 1895.)

9 Shets-Sheet 6 lA/VE/VTORJ:

77 T M m c m: mums PETERS co, r-umouwo WASHINGTON. a

Patented Jan. 23, I900. w. 0 c. SELLERS 0 w. LEWIS.

HYDRAULIC PRESS.

(Application filed July 1!, 1895.)

9 Sheeis-Sheet 3,

(No Model.)

No. 642,009. Patented Jan. 23. I900. W. &. C. SELLERS & W. LEWIS.

HYDRAULIC PRESS.

(Application filed July 11, 1895.) (No Model.) 9 Sheets-Sheet 9.

FIE. El-

W/TNE s5 #vmrofis: W I

w: mums PETERS co, now-urns wAamNnroN, 04c,

Thurman STATES PATENT FFICE.

.DELPHIA, PENNSYLVANIA, .ASSIGNORS TO TIIE \VILLIAM SELLERS &

COMPANY, INCORPORATED, OF PHILADELPHIA, PENNSYLVANIA.

HYDRAULIC PRESS.

sincrrron'rrou forming part of Letters Patent No. 642,009, dated January23, mod

Application filed July 11, 1895. Serial No. 55.5;662. (N model.)

To all wit/mt it Uta-y concern:

Be it known that we, WILLIAM SELLERS, COLEMAN SELLERS, and WILF'REDLEWIS, of the city and county of Philadelphia, in the State ofPennsylvania, have invented certain new and useful Improvements inHydraulic Presses, of which improvements the following is aspecification.

The form of press which is the subject of our invention is adapted to avariety of purposessuch as forging, coining, stamping, punching, andshearing, in which great pressure and rapidity of action may be requiredwith movements controlled by hand or automatically. Machinery of thisclass is comparatively new and has been applied more particularly tohydraulic forging, for which purpose the form of press best knownconsists of a lower head or base upon which the anvil is supported, anupper head which carries the forging-ram, and cylindrical columns whichconnect the two heads together and by their tensile strength resist theforging-pressure of the ram. The upper head is adjustable verticallyupon these columns and may be set close to the work, so that with theshort stroke to which this press is limited the forging-ram may beguided by the cylinder in which it moves, and no other guide isprovided. It is apparent that with a ram so guided a long stroke wouldbe inadmissible, and even with a short stroke it will be observed thatthe guiding length of the ram is least when the greatest lateral supportis required. The power to operate the press is derived from pumps at aconsiderable distance, which, with their fly-wheel connectious, are inconstant motion, delivering water into a circulating-pipe which leads toand from the press, and in so doing they perform no work other than thatrequired to overcome the friction of their moving parts and of the waterin the pipes. Near the press is a defiectingvalve operated by hand,which when open permits an unobstructed flow from and to the pumps, butwhen closed the current from the pumps is deflected into the cylinderwhich carries the forging-ram, forcing it down upon the metal to beforged and continuing to press upon it so long as the deflectingvalve isclosed and the pumps continue to operate. It will be observed, however,that the work performed by the pumps will be exactly proportioned to theresistance, and

as it rarely happens that this resistance can be prolonged the flywheelwill give out the force stored up in it, so that the steam-pres sureneed not be greatly augmented to produce the proper forging effect, anda high degree of economy is thus attainable. The upward or return strokeis effected by a constant pres sure from an accumulator acting upon drawback plu ngers on each side of the forging-ram. The draw-back pressurethus acts like a counterweight to resist the downward stroke of theforging-ram, and it becomes operative to raise this ram as soon as thedeflecting-valve is opened to relieve the pumping-pressure. This form ofpress may be designated as the single-acting system with continuousflow, the pumping-pressure being exerted to force the ram in onedirection only. In this form of press the forging-ram beingcounterbalanced and forced downward by the pumps alone its descent isnecessarily slow, and alater form of press has been designed to remed ythis defect. In this later press the pressingcylinder is above, asbefore, but the pumps are arranged to force the forgingram upward aswell as downward, so that when the liftingpressure is released theforging-ram will not only drop byits own weight, but being connectedwith a pressure-reservoir through large pipes it is assisted in itsdescent by the water which flows on the top of this ram and fills thecylinder ready for pumpingpressure, which is then applied until theforging-ram has pressed the metal it is operating upon to the desiredextent. The pumps are then stopped, the valves reversed, and the pumpsagain started, discharging fluid into the lifting-cylinders, which beingsmall, as compared with the pressing-cylinders, the ascent may be asrapid as the descent, the Water in the pressing-cylinder being forcedback into the reservoir ready for the next descent of the forging-ram.In this system the press to resist lateral strains.

ever, is long enough to admit of all the adjustment required, so thatthe movements of the ram are not only more rapid, but its adjustment tothe proper height can be more readily effected than in the first system.In this latter system the pressure-pumps act to drive the forging-ram inboth directions, and it' may therefore be designated as double act-ingfibut the flow is not continuous. The pumps must be started and stoppedfor every stroke, and it is more properly designated, therefore, as adouble-acting system with intermittent flow. To such asystem there areveryserious objeotions,for although provision has been made for a quickmovement of the forging-ram in both directions and for requiring lesspumping capacity the number of manipulations are so much increased thatthe number of strokes per minute are probably decreased, and as nofly-wheel can be used and the steam cannot be worked expansively it willfall below the first system in economy also.

Another and a later form of press has been designed in which theoperating-cylinders are placed in the lower head and motion iscommunicated to the forging-ram in the upper head by movable uprightssliding through bearings in the lower head. High and lowaccumulatonpressures are used and provision is made for rapid movementof the forgingram to and from its work; but the manipulations areexcessive, the flow is not continuous, and it belongs to the class lastdescribed and is subject to the same disabilities.

One object of our invention is to operate the press by pumps runningcontinuously and to govern the movements of the pressing-ramautomatically or by hand at will so as to attain the greatestexactitudein its work with the greatest rapidity in its operationwithout diminishing the control of the oper- 'ator.

It is a further object to provide means for adjusting the stroke of thepressing-ram while itis working automatically so as to determine thesize of the work to the greatest n'icety.

It is a further object to provide means for limiting the stroke of thepressing-ram to the attainment of any desired pressure; and it is afurther object to obtain the necessary movementof the pressing-ram inboth directions in the shortest possible time without increasing thecapacity of the pump beyond that required for the rate of movement inpressing.

To these ends the nature of our invention consists in an automatic valvecom m unicating between the pressing-cylinder and a supply-tank, wherebycirculating fluid may be rapidly admitted to and discharged from thepressing-cylinder when the actuating fluid is directed to thepressing-ram or to the liftingrams.

Itfurther consists in a pilot-valve and an automatic stop-motion bywhich the operating-valve may be controlled from the pressing-ram torepeata given stroke with precision.

It further consists in a pilot-valve and an adjustable safety-valve bywhich the operating-valve may be controlled to repeat a given pressurewith precision.

It further consists in a latched hand-lever in connection with theautomatic motion by which the press may be thrown at once from automaticto hand control, or vice versa.

To facilitate the description, we have designated the fluid deliveredfrom the pumps as ing employed when arranged to operate by" hand only.Fig. 2, Sheet 2, is a side elevation of the press shown in Fig. 1; andFig. 3 is a vertical section on the center line of Fig. 2, showing thepressing and lifting rains, valves, and piping, the pilot-valve andautomatic mechanism being omitted for the sake of clearness, andthepress is shown as operated entirely. by hand. Fig. 4,.Sheet 3, is a planof the operating-valve. Fig. 5 is an elevation of the same, showing insection one of its circular slide-valves controlling the How of theactuating fluid. Fig. 6 is a section on the center line of Fig. 5, andFig. 7 is a section on the center line of Fig. 4. Fig. 8 is a plan ofthe slide-valve in chamber 42, Fig. 5; and Fig. 9 is a plan of theslide-valve in chamber 43, Fig. 5. Figs. 10 and 11 are enlarged views ofthe valve-seats for Figs. 8 and 9, respectively, showing in broken linesthe position of the valves when set in their middle position to sustainthe ram and allow the circulating fluid to pass through. Figs. 10 and 11show the position of the valves when moved to direct the actuating fluidinto the pressing-cylinder to depress the ram. Figs. 10 and 11 show theposition of the valves when moved to direct the actuating fluid into thelifting-cylinders to raise the ram. Fig. 12, Sheet 4, is a sectionalelevation of an automatic supply and exhaust valve. Fig. 13 is a plan ofthe valve, and Fig. let a plan of its seat. Fig. 15, Sheet 5, is a frontelevation of'the pilot-valve, operatingvalve, and the mechanism, partlyin section,

IIO

between them to control the operating-valve automatically. Fig. 16 is aside view of the same, and Fig. 17 is a sectional elevation of thepilot-valve. Fig. 18, Sheet 6, is an enlarged view of the mechanismshown in Fig. 5, showing more particularly and in section the operatingand safety valve in connection with the pilot-valve to workautomatically up to any predetermined limit of pressure. Fig. 19, Sheet7, is an elevation in section of a forging-press, showing the piping andvalves arranged for automatic or hand control. The lifting-cylinders areabove the cross-head instead of below it, as shown in the medal-press,and the operating-valve is designed for water instead of oil. Fig. 20,Sheet 8, is a vertical section through the operating-valve, showing thevalve as set to sustain the pressing-ram and to permit an idlecirculation of the water pumped. Fig. 20 is a similar section showingthe valve as set to depress the pressing-ram, the actuating fluid beingdirected to the pressing-ram while the water in the lifting-cylindersescapes to the tank. Fig. 20 is a similar section showing the valve setto raise the pressing-ram, the actuating fluid being directed to thelifting-rams while the water in the pressing-cylinder discharges intothe tank. Fig. 21, Sheet 9, is a sectional elevation of an alternateform of the automatic supply and exhaust valve.

Referring to Figs. 1,2, and 3, 1 is the upper or cylinder head, in whichthe pressing-cylinder 2 is carried. 3 is the lower or anvil head, uponwhich the anvil 4 is supported. 5 and 6 are columns separating the headsof the press, and 7 and 8 are bands compressing them firmly upon thecolumns. 9 is the automatic valve, attached to the pressing-cylinder 2and shown more particularly in Fig. 12. 10 is the operatingvalve. (Shownalso in Figs. 4, 5,6, 7, 8, 9, 10, and 11.) 11 is the pressing ram, and12 and 13 are the lifting-rams, both guided by the cross-head 14,attached to the pressing-ra1n 11 and guided in the uprights 5 and 6. 15and 16 are the lifting-cylinders. 17 and 18 and 19 and 20 are blocks orwedges through which the tension on the bands is resisted by thecolumns. The cylinder-head l, anvil-head 3, cylinder 2, columns 5 and 6,and tensile members or bands 7 and 8 are assembled by placing them inposition, as shown, with the pressing-ram blocked up on the anvil-head,so that by admitting fluid-pressure to the cylinder 2 the cylinder-head1 and anvil-head 3 will be forced apart. This fluidpressure ispreferably adjusted at fifty per cent. in excess of that at which thepress will be worked, and while so adjusted the blocks or wedges 17, 18,19, and 20 are inserted and secured by the bolts (6 a to the columns 5and 6, so that when the fluid-pressure is removed the columns mustsustain the tensile strain of the bands 7 and 8, thereby maintaining anydesirable strain in the bands 7 and Sand rendering the whole structureextremely rigid. The blocks 17, 18, 19, and 20 are represented in thedrawings as wedges, but for large presses parallel blocks fitted to theopenings when the maximum strain is applied will be safer, as lessliable to be displaced. 21 is a drip-dish to catch any leakage from thepress ing-cylinder, and 22 is a reservoir in the lower head into whichall leakage is drained. 23 is a tank at a convenient elevation,containing the working fluid. 24 is a valve by which the in g or generalrepairs.

inders of a three-throw pump, which receives its supply from the tank 23through the pipe 26 and discharges it through the pipe 27 into theoperating-valve 10. 28 is a pipe communicating between the valve 10 andpipe 26, through which pipe the actuating fluid passes when the pump isoperating while the rams are not operating, and this whatever theposition of the rams when their movement is arrested. 29 is a pipecommunicating between the operating-valve 10 and the automatic valve 9,through which pipe the actuating fluid passes to force the pressing-ramdownward. 30 is a pipe communicating between the operating valve 10, thelifting-cylinders, and the automatic valve 9, through which pipe theactuating fluid passes to the lifting-cylinders to raise thepressing-ram. 31 is the operating hand-lever, attached to the rockshaftThis shaft carries the arms 33 and 34, which connect by the links 35 and36 with the arms 37 and 38 on the valve-stems 39 and 40.

The operating-valve (shown in Figs. 4, 5, 6, 7, 8, 9, 10, and 11)consists of the body 10, in which the chambers 42 and 43 are formed toreceive the circular slide-valves 44 and 45 on the stems 39. and 40.These stems are coupled, as described, to move together and maintain thevalves 44 and 45 in the same relative positions. The actuating fluid isre ceived in the chamber 42 through the pipe 27 and passes in theposition shown in Fig. 10 by way of the holes 47 and 48 under the valve44 and out through the opening to the passage 50, Fig. 6, and thencethrough the passage 51 to the pipe 28 and back to the pumps or to thetank 23. The hole 47 passes directly through to the chamber43, Fig. 7,andis covered by the valve 45, Fig. 5. The fluid in this chambersustains the pressing-ram and may escape through the plug 52 when thevalve is moved to uncover it, so that when the plug 52 is covered by thevalve 45, as shown in Figs. 10 and 11, the pressing-ram will besustained and the fiow from the pumps will be discharged under the valve44, as previously described. The size of hole in the plug 52 isproportioned to the speed of descent required in the pressing-ram, andas the plug is removable the speed is thus easily adjusted. To avoid thepossibility of entraining air, it is desirable to limit the speed ofdescent by the ability of the supply tank and pipes to fill thepressing'cylinder without a partial vacuum being formed, and by varyingthe size of the opening in this plug the highest practicable speed canbe eXperi mentally determined. The passage through the plug 52 leads tothe passage and thence to the tank. 53, Fig. 6, is apassage from thechamber 43, Fig. 7, to the small safety-valve 54, Fi 6, its object beingto relieve the lifting-cylinders of undue pressure when the outletthrough 52 is suddenly closed by the valve 45. 55 is the stem. of anadjustable safety-valve seated against the operatingpressure through thepassage 56, Fig. 6. This passage is enlarged above the valve-seat, andthe stem 55 fits loosely therein, so that when the valve begins to opena larger area is at once exposed, thus causing it to open wide andremain open under areduc'ed pressure. To prevent pounding, thevalve-stems 54 and 55 are provided with collars, as shown, around whichthe fluid must leak,produc'ing slow and steady movements. The valve-stem55 is loaded by the spring 57, resting on the washer 58 and abuttingagainst the abutment-bolt 59 in the adjusting-nut 60, which surroundsthe springcase 61, attached to the valve-body 10. The lower edge of thenut 60 is graduated, and when set for any desired pressure it may beheld in position by the lock-nut 62 on the bolt 59, the latter beingkeyed, as shown, to the spring-case 61. The operating slidevalve isshown and described in a compact and convenient form, particularlysuitable for the use of oil as the actuating fluid. No packing isrequired for the valve-seat, and when properly lubricated slide-valvesare preferable to piston -valves, which depend upon packing for theirproper performance of duty. In large forging-presses, however, Wherewater is used as the actuating fluid a slide-valve is not desirable onaccount of the difficulty of lubrication under large surfaces and heavypressures. For such cases the piston-valve shown in Fig. 20 ispreferable. For the sake of clearness the packing for this valve hasbeen omitted, as it is well known and in common use for hydraulic valvesof the Finby type and because, as in the slidevalve just described, ourimprovement does not consist in the packing, but in the means adopted toraise, depress, or sustain the ram in connection with a pump, which musthave a constant outlet for its continuous discharge, although thisdischarge may or may not be at a constant rate. The discharge from thepumps enters the valve-body 110 through the pipe 27 and is notinterrupted for an instant as the valve moves into any of the threepositions shown. In Fig. 20 the discharge passes into the pipe 28,communicating with the tank. In Fig. 2O it passes into the pipe 29,communicating with the pressing-ram. In Fig. 20 it passes into thelifting-cylinder through the pipe 30, and as the outlet to the tankcloses the valve to the lifting-ram opens, so that for an instant thefluid begins to enter the lifting-cylinder before it stops flowing tothe tank. Thus a contin nous discharge from the pumps is provided for inevery position of this piston-valve, as well as in the slide-valvepreviously described. lVhen set, as shown in Fig. 20, to dischargeagainst the pressing-ram, the lifting-cylinders exhaust to the tankthrough the pipe 28, in which the open plug 41 is inserted to regulatethe speed of descent. In taking this position it is proper to note thatthe exhaust begins before the flow to the pressing-ram isfullyestablished; otherwise the lifting-cylinders might be ruptured bythe action of the pumps on the pressing-ram.

In the operating slide-valve first described We have two valve-chambers,one of which, 43, receives the actuating fluid through the other chamber42 and controls the exhaust from the lifting-cylinders, while thechamber 42 receives a constant supply of actuating fluid from the pumpsand discharges it into one of three passages leading to the tank, thepressing-cylinder, or the valve-chamber 43. The valves 44 and 45,covering the ports in the chambers 42 and 43, are made to slide on theirseats together by the oscillation of the valve-stems 39 and 40, coupledto the rock shaft 46, to which the hand-lever 31 is attached. Thus whenport 48 is closed, as shown in Figs. 10 and 11 the actuating fluid mustescape from the chamber 42 by the passage 47, and thence to thelifting-cylinders, raising the ram, and when the port 47 is closed, asshown in Figs. 10 and 11, by the valve 44, the actuating fluid mustescape by the port 48 into the pipe 29, and thence to thepressing-cylinder, while at the same time the port 52 is uncovered bythe valve 45 to allow the fluid in the lifting-cylinders to escape backinto the tank. The same fluid is thus used over and over again and nowaste except leakage or evaporation can occur. Other fluids than watermay therefore be used to advantage, and this valve, as shown anddescribed, is designed especially for oil. When water is used,lubrication of a slide-valve becomes more difficult and the piston formof valve with leather packing, as shown in Fig. 20, is preferable; butwhatever particular form the valve may take it must have the capacity toreceive and to direct in any one of three different directions all ofthe discharge from the pump without for an instant interrupting thecontinuity of its flow. Referring to Figs. 20, 20, and 20 110 is thevalve-body, and the pipes connected therewith lead to the differentparts of the system, as indicated. 111 is the piston-valve, and, asshown in Fig. 20, the pump, pressing-ram, and tank are all incommunication with each other, while the water in the lifting-cylindersis locked up, so that the pressing-ram will stand in any position it mayhave assumed when the valve was moved to the position shown in Fig. 20.Other parts corresponding to those shown in Figs. 7 and 5 have beendesignated by the same numerals, and an inspection of the valve in itsthree positions will show that the same result has been accomplished asdescribed for the operating slidevalve. By means of either form ofoperating-valve we can therefore direct an actuating-stream of fluidfrom a pump to the operations of a press, so as to limit the load uponthe pump to an unobstructed circulation of the fluid when the press isat rest and when it is at work to the raising of and to the depressionof the rams. To economize for the actuating fluid.

time, however, rapid movements of the pressing-ram to and from its workare desirable, and to this end the automatic supply and exhaust valve(shown more particularlyin Figs. 12, 13, and 14) has been introduced.The function of this valve is to open and to close communication betweenthe pressing-ram and the tank. It does not affect the operation of thepump in any way, and it forms no part of the pump and valve system. 9 isthe valvecase, extending into the pressing-cylinder 2 and secured by thenut 63 to the upper head 1, Fig. flat is the automatic supply andexhaust valve, fitted in the upper part of the valvecase and guided atits lower end by the stem 65 in the valve-seat spider 66. 67 is a plugclosing the outer end of the valvecase, through which the actuatingfluid is admitted from the pump through the con duit 29. 68 68 arepassages in the valve 64, through which this fluid passes to thepressingcylinder. The passages 68 68 through the valve 6i simply aitordan uninterrupted passage at all times that a passage is required Forthis purpose it is not requisite that the passage shall be through thevalve 64. Any conduit that will deliver this fluid from theoperating-valve,

above as well as below the valve 64 when it is seated would answer thepurpose, and to illustrate this we have shown by dotted lines on Fig. 12such a connection as a substitute for the passages 68 68 through thevalve 6%. The conduitwhich connects the pump with the pressing-cylindermay enter the cylinder direct, orit may enter the valve-case 9 below thevalve 64. In either case the passages 68 6S serve to carry the pressurein the pressingcylinder through the valve 64: to its enlarged upper end,and thereby hold it down upon its seat. 69 is a piston fitted in thevalve-stem chamber 70 to act against the stem and raise the valve 6twhen pressure is admitted through the pipe 30, which communicates withthe lifting-cylinders 15 and 16. This piston 69 is packed at the top, asshown, to prevent the pressure-water from the lifting-cylinders escapingaround the piston without raising it and the valve Cl. The lower end ofthe piston 69 forms a valve which when seated prevents the pressure ofwater under the valve 64, when it is seated on the spider 66, fromescaping around the stem 65 into the pipe 30. This pressure continues tosustain the valve 6% in the position shown so long as thelifting-cylinders support the weight of the pressing-ram, so that alarge volume of fluid may pass under the valve 64 to and from the tankwithout obstruct-ion;- but when the downward movement of the ram isarrested by striking the anvil or a piece of work resting upon it thelifting-cylinders are thereby relieved of pressure and the valve 64:descends to its seat upon the spider 66, shutting olt comm unicationthrough the pipe 26 with the tank, while the actuating fluid from thepumps passes through the holes 68 68 and performs the work of pressingor shaping the material under the dies. The upper end of the valve 64 isslightly larger in diameter than its seat, to make it close tightly onthe valve-seat 66. When pressure is again admitted to thelifting-cylinders for the return stroke of the ram, this pressureoperates through the pipe 30 to raise the valve 64; but its rise islimited by the ring 71 abutting against the ring 72, which are formed toinclose a small quantity of fluid and act as a dash-pot. The seat ofvalve (it is similarly protected against pounding, and rapid movementsof this valve are thus permissible without injury. The actuating fluidflows through the valve 64 and the circulating fluid flows under thisvalve while the pressing-ran1 is descending to its work. After thepressing-ram has reached its work, which, as above described, closes thevalve 64, no time is lost in continuing the descent of the pressing-ramby the actuating fluid which is flowing through the valve 64, until by amovement of the operatingwalve the actuating fluid is directed under thelifting-rams, the cylinders of which being much smaller in diameter thanthe pressing-cylinder, the pressing-ram is returned quickly, so thatrapid movements in both directions are obtainable, while the power andtime are economized in the operation of the press.

In the alternate form of automatic valve shown in Fig. 2i the connectionbetween the valve 64 and the lifting-cylinders 15 and 16 is dispensedwith, and instead of the single valve 64, operated by the pressure inthe lifting cylinder, we have the two checkvalves, as shown, opening inopposite directious, one of which admits tank-water to thepressing-cylinder and the other allows the cylinder to discharge rapidlyback to the tank. As shown in Fig. 21, the actuating fluid may passthrough the valve 64 by the holes 68 68, or it may pass through anoutside conduit, as indicated in Fig. 12 by dotted lines. The holes 6868 are made, preferably, of small area to restrict the flow through themfrom the pressing-cylinder and allow the valve to open freely; but largeholes provided with check-valves or a loose disk to cover all the holesand opening outward, as shown bydotted lines in Fig. 21, may be used ifthe conditions are such as to make the resistance of these holes worthconsidering. The passage 29 communicates with the tank when the rise ofthe pressing-ram lifts the valve 64-, and the two valves 64 and 112 actexactly like the valves of a pump, drawing in through one anddischarging through the other. Whether the pressing-ram is provided withthe two valves above described or with the'one valve previouslydescribed, it acts as a pump at every stroke, drawing the fluid after itas it descends, whether the source of supply is above or below it, anddischarging the fluid as it is raised by the lifting-rams; but whenstand 76, bolted to the upright 5.

. upon it the lug 86 to engage with the toe 87 I the Valve 64 is raisedby the pressure under the lifting-rams the flow of fluid to and fromthis pump is unobstructed, while with the two valves last described thisflow is obstructed by the tension of the spring, which closes theinduction-valve in one case and the weight of the eduction-valve in theother.

For the system illustrated in Fig. 1 the manipulation of theoperating-valve requires close attention, and for certain purposes,wherethe stroke of the pressing-rain must be made and repeated withprecision, a system of automatic control is desirable. For this purposethe operating-valve must not only be moved its full stroke for eachreversal of the pressing-ram, but this movement must be effected by someforce that will continue in operation after the pressing-ram has come torest. Otherwise the ram will be liable to stop at the end of its stroke.

Referring to the system of automatic control illustrated in Figs. 15,16,and 17 and further detailed in Fig. 18, 73 is a rack attached to thecross-head 14 and engaging the spur-wheel 74 on the shaft 75, carried inthe 77 is a bevel-wheel with an outer clamping-rim centered loosely onthe'shaft and engaging with the pinions 78 and 79, carried in the frame80, which is keyed to the shaft 75. 81 is a bevel-wheel centered looselyon the same shaft and engaging also with the pinions 78 and 79. 82 is aworm-wheel securely attached to 81 and engaging with the Worm 83 on theshaft 84, to which the indexed hand-wheel S5 is attached. The outer rimof '77 has formed .on the rocker-arm 88, attached to the stem of thepilot-valve 89. The stop is adjustable on the rim of 77, and whenclamped in any given position engages with the toe 91 on the rocker-armS8. The pilot-,valve 89, Fig. 17, consists of the chamber 92, throughwhich the actuating fluid is made to pass, and the plungers- 93 and 94,to either of which pressure is admitted by the movement of the circularslide-valve 95 on the valve-stem 96, to which the rocker-arm 88 isattached. The plungers 93 and 94 are yoked together by the cross-heads97 and 98 and the bolts 99 and 100. The cross-head 98 is connected bythe link 101 with the operating-valve lever 102, which is expanded atone end to form a segment and notched to receive the latch 103 on thehand-leverlOat. Both levers 102 and 104: are pivoted on the same stud105, and the hand-lever 104 is bent to form a bell-crank for attachingthe link 36 to communicate motion to the arm 38. The pilot-Valve 89 isinterposed between the circulating-p11 mps 25, Fig. 1, and theoperating-valve 10, and the valve-chamber 92 may be regarded as anenlargement in the pipe 27, through which the actuating fluid is made topass. 106 and 107 are openings to the plungers 93 and 94, which areshown as covered by the valve-seat 95.

114 is an opening under the valve-seat 95, which permits the fluid ineither chamberof 93 or 94 to escape into the pipe 26, communicating withthe tank when the actuating fluid is admitted to the other chamber. Itwill now be seen that as the cross-head 14.: moves down the wheel 77will rotate and the stop 90 will act against the toe 91 on therocker-arm 88, shifting the valve-seat 95 to admit pressure on theplunger 94: and exhaust from the plunger 93. The yoke 98 and link 101will thus be forced down as far as it can go, and the operating-valve 10will be set to admit the flow to the lifting-cylinders. As thecross-head moves up the wheel 77 will be rotated in the same directionas 714; at twice its rate of speed until the lug 86 acts against the toe87 on the rocker-arm 88, moving the valve-seat 95 to admit pressureunder the plunger 93, reversing the operating-valve and the movement ofthe pressing-ram. The pressure in the valve-chamber 92 must exceed thepressure in the pipe 26 by the amount required to overcome the fluidfriction in the pipes, and when work is being done in either directionthis excess of pressure may be very great; but when the excess is smallthe resistance of the operating-valve is also small, and when large thework to be done is proportionately great. It is not impossible tooperate the valve 10 directly from the stops on the rim of 77; but it isdesirable that when the operat-ing-valve is set for movement in eitherdirection the ports shall be fully opened, and this purpose isaccomplished by the intervention of the pilot-valve, which must alwaystake an extreme position and carry with it the operating-valve. It isevident that the length of stroke on the cross-head 14 can be accuratelydetermined by the position of the stop 90, and it will be seen that thelocation of this stroke is determined by the wormwheel 82 and itsindexed hand wheel 85, while the length of the stroke is determined bythe distance between the movable stop 90 and the fixed stop 86 on theframe 80. The bevel-wheel S1, to which the worm-whee1 82 is attached,acts as an abutment for the pinions 78 and 79, and as the abutment movesthe relation between the wheel 77 and the cross-head 14c varies. Thuswhile the crosshead is running "automatically on a given length ofstroke the distance between dies atthe end of the downstroke can beaccurately measured and controlled, and by means of the mechanism justdescribed the operator is enabled to combine the rapidity of automaticaction with the utmost nieety of adjustment. For this purpose theepicyclic train is particularly well adapted, for by its use the meansfor adjustment is always convenient, while the rate of movement of thestops may be greatly varied from that of the cross-head. As shown anddescribed, the diameter of the circle in which the outer ends of thestops travel is nearly double the diameter of the IIO pinion which gearswith the rack on the crosshead, so that from this cause alone the stopswill travel nearly twice as fast as the crosshead; but as this epicyclictrain is shown and described, the stops will make two revolutions forone of the pinion, so that, as shown, the stops will travel nearly fourtimes faster than the cross-head. If, however, the frame 80 should becentered loosely upon the shaft 75 and this frame should be arrangedtocarry the stops now carried by the wheel 77 and 77 should be keyed tothe shaft 75, the frame 80 would only revolve at one-half the rate ofthe wheel 77 and the stops would then travel at nearly the same speed asthe cross-head. By means also of the latched lever lOt the automaticcontrol may be at once cut loose and the press may then be operatedentirely by hand. When so operated, the movement of the pilot-valve hasno effect, because it is cutloose from the operating-valve. The toes 87and 91 are each hinged on an end of the rockenarm 88, so that either canswing toward the other without moving the rockerarm. if either stop 86or 90 is between the toes 87 and 91 and is pushed against either toe, itwill carry the rocker-arm with it until the stop will pass under the toeit is moving. If then the wheel 77, with its stops 86 and 90, continuesto move in the same direction, the next stop will come in contact withthe back of the other toe, raise it, and pass under it without movingthe rockeuarm, and as the other toe is already raised, so that the stopswill pass under it, the rocker-arm will not be moved until the directionof rotation of the wheel 77 is reversed.

For the purpose of hydraulic forging the mechanism shown in Figs. 15,16, and 17 is sufficient for allrequireinents; but for stamping andcoining, where a definite pressure is desired rather than a definitemovement, the press may be run automatically by the attachment shown inFig. 18. Here the stem of the safety-valve is extended and carried upthrough the bolt 59 to act against the lever 108, which is connected bythe link 109 with a projection on the rocker-arm 88. The lug 86, actingagainst the toe 87, limits the upward movement of the cross-head, andwhen a given pressure is attained on the down stroke the safety-valveblows off, impinging against the leverlOS and reversing the movementautomatically.

In Fig.19 the arrangement of parts has been determined especially withreference to hydraulic forging, the lifting-cylinders 15 and 16 beingplaced above and away from the heat of forging, while a cylinder of longstroke 2 is used for adapting the press quickly to work of variabledimensions. Here the operatingvalve 110,Fig.20, is shown coupled to thepilotvalve 89, Fig. 17, and the pipes are connected as previouslydescribed for automatic action.

The automatic mechanism shown in Figs. 15 and 16 has been omitted forthe sake of clearness, but it is applied as shown in Figs. 15 and 16,and derives its motion from the rack 7 3, which in this case is attachedto one of the suspension rods which connect the lifting-rams with thecross-head.

It is evident that the safety-valves shown in Fig. 6 and the specialfeature of the safetyvalve shown in Fig. 18 are applicable alike toeither form of operating-valve, and that although not shown inconnection with the piston-valve they are intended to be used therewithwhenever required.

The operation of a press embodying our improvements may now be describedby reference to Figs. 1 and 19. \Vhen operated by hand, as shown in Fig.1 and further detailed in Figs. at, 5, 6, 7, and 12, the actuating fluidflows from the pumps 25 25 25 through the pipe 27 to the operating-valve10, and when the operating lever stands, as shown, in its middleposition the flow continues through the pipe 28 and back to the pumps.At the same time the fluid in thelifting-cylinders is locked up and therain remains at rest in whateverposition it maybe. Now when thehandlever is pushed down the fluid in the lifting cylinders will exhaustthrough the pipe 28, letting the ram descend, while the circulatingfluid flows into the pressingcylinder through the automatic valve 9,which is held open by the pressure required to force the fluid in thelifting-cylinders through the contracted outlet in the operating-valve.At the same time the actuating fluid is passing through the pipe 29through the automatic valve into the pressing-cylinder, and as soon asthe ram meets resistance, checking its movement, the pressure whichsupports the automatic valve is withdrawn and it closes, while the ramcontinues to advance by the actuating-fluid alone. Having finished thestroke at the pressure desired for striking a medal or for coining, theadjustable safety-valve blows off, which raises the hand-lever, and theoperating-valve is thereby set to direct the actuating fluid into thelifting-cylinders and open communication between the pipes 29 and 28.The pressure thrown into the liftingcylinders at once opens theautomatic valve and allows the fluid in the pressing-cylinders todischarge without obstruction into the tank. Having finished the returnstroke,the hand-lever may be brought again to its middle position andthe pumped fluid returns to its original circulation through the pipes27 and 28. If through carelessness the return stroke is continued untilthe pressing-ram stops against its end of the cylinder, the smallsafety-valve 5i, Fig. 6, opens and no damage occurs.

Referring now to Fig. 19, in connection with Figs. 12, 15, 16,17, 18,and 20, the automatic operation of the forging-press can be readilyunderstood. The pumps 25 25 25 receive, as

before, a supply of fluid through the pipe 26 and discharge it throughthe pipe 27, which now passes to the pilot-valve and thence to theoperating-valve instead of directly to the operating-valve, as before.Vith the operating-valve set in its middle position, as shown,circulation takes place through the pipes 28 and 26 back to the pumps,while the pressing-ram is at rest, sustained either by the work or bythe Iiftingrams. The pressing-ram is now at the end of its downstrokeand may be supposed to be at work forging, the pilot-valve has beenshifted by the automatic mechanism, and the plunger 94:, Fig. 17, isnowmoving the operatingvalve into the position shown in Fig. 20". When thisposition is reached,.the actuating fluid passes into thelifting-cylinders, the valve 64: will be raised by the pressure from thelifting-cylinders, and the pressing-cylinder will then discharge intothe tank WltllOllt obstruction as the pressingram is raised. Havingmoved a certain distance, determined by the adjustment of the stops 86and 90, Fig. 16, the stop 86, acting against the toe 87 of therocker-arm 88, moves the pilot-valve and admits pressure against theplunger 93, which immediately sets the operating-valve in the positionshown by Fig. 20. The lifting-cylinders will now exhaust to the tank andthe pressing-ram will descend until the forging-die strikes the work.Its cylinder will be filled through the pipe 26 from the tank and by theactuating fluid which passes into the tank-supply through the passagesin the valve 64. Then the forging-die strikes the work, the pressure onthe lifting-cylinder is relieved and the valve 6% will closeimmediately, when the ram will advance to its work by the action of thepumps alone. In this way the press will continue to run automatically,and while thus running on a given length .of stroke the position of thatstroke can be varied as desired by means of the indexed hand-wheel 83,so as to accurately determine the size of the work. WVhenever it isdesired to stop, the automatic mechanism is disconnected by the latch103 on the hand-lever 104 and the press comes entirely under handcontrol.

Having thus described our invention, what we claim as new, and desire tosecure by Letters Patent, is

1. In a hydraulic press, a lifting-ram, a pressing-ram, a pump and atank, in combination with a valve which deflects the liquid flow fromthe pump, to the lifting-ram, to the pressing-ram, to the tank, locksthe liquid under the lifting-ram, and maintains at all times an openpassage for the flow from the pump, and means'which provide an openpassage from the tank and from the pump to the descending pressing-ram,and automatically closes the passage from the tank to the pressing-ramwhen the descent of the ram is retarded by an obstruction which willsustain its weight.

2. In a hydraulic press, a lifting -ram, a pressing-ram, a pump and atank with mechanism to deflect the liquid flow from the pump to thelifting-ram, to the pressing-rain, to the tank, to provide at all timesan open passage for the flow from the pump, in combination with areciprocating hydraulic plunger which operates the mechanism, and thepilot-valve which determines the direction of the flow from the pump tothe hydraulic plunger.

3. In a hydraulic press, alifting-ram, a pressing-ram, a tank and apump, a valvecase provided with a port, which receives the flow from thepump, and ports which discharge it to the lifting-ram, the pressing-ramand the tank, respectively, in combination with a valve which moveswithin the valvecase, and deflects the flow from the pump, to thelifting-ram, to the pressing-ram, and directly to the tank, withoutpassing to the pressing-ram or to the lifting-ram, seriatt'm, incombination with a reciprocating hydraulic plunger which operates thevalve, and the pilot-valve which determines the direction of the flowfrom the pump to the hydraulic plunger. I

4. In a hydraulic press, a pressing-rain, a pump and a tank, avalvewhich controls the admission from the tank to the pressing-ram and anopen passage connecting opposite ends "of said valve, in combinationwith a conduit between the pump and the pressing-ram.

5. In a hydraulic press, a pressing-ram, a lifting-ram, a tank and apump, in combination with a valve the seat end of which is smaller thanthe other end and which controls the admission from the tank to thepressing-ram, an open passage connecting opposite ends of said valve, aconduit between the pump and the pressing-ram, and a conduit between thevalve and the lifting-ram whereby the valve willbe raised and sustainedby fluid-pressure under thelifting-ram, seated by gravity and lookedupon its seat by fluidpressure upon the pressing-ram.

6. A hydraulic operating valve, consisting of two valvechambers with avalve in each, the valves so connected that they must move together overtheir respective ports, in combination with a conduit which connects aport over which the valve in one chamber moves, with a correspondingport in the other chamber.

7. In a hydraulic press, a pressing-ram, a lifting-ram, a tank and apump, an operating-valve movable by a reciprocating hydraulic plunger,and a pilot-valve which determines the direction of the flow from thepump to the hydraulic plunger, in combination with an epicyclic train,one member of which is driven from a reciprocating part of the press,another member is adjustable about a shaft in the axis of the train, anda third member is provided with stops which actuate the pilot-valve.

8. In a hydraulic press, a pressing-ram, a lifting-ram, and anoperating-valve, an adjustable safety-valve, and a pilot-valve, incombination with mechanism operated by a IIO ram of the press whichmoves the pilot-valve in one direction, and a system of levers actuatedby the adjustable safety-valve which moves the pilot-valve in theopposite direc- 5 tion.

9. A hydraulic operating-valve, provided with a latehable lever formoving the valve by hand, in combination with a lever vibratable aboutthe fulcrum of the latchable lever,

10 and connected to a reciprocating hydraulic plunger operated by apilot-Valve which determines the position of the operating-valve, withmeans for latching together or unlatching the two levers at will.

WM. SELLERS. COLEMAN SELLERS. WILFRED LEWIS. Witnesses:

JOHN L. PHILLIPS, E. R. HARPER.

